Saturday, 27 September 2014

Misrepresentation of kin selection by group selection advocates

Group selection enthusiasts have repeatedly argued that: kin selection can only explain cooperation between close relatives; that humans cooperate in groups in which the humans are not closely related. Since kin selection can't have been responsible, group selection is needed.

Kin-based mechanisms should be designed to focus benefits only on close relatives, and thus kin selection does not help us to solve the problem of cooperation among large groups of unrelated individuals unless our kin-psychology is making a lot of big mistakes by confusing large numbers of non-relatives and strangers with close relatives.

Cultural kin selection is based on shared memes - not shared genes. Cooperation between strangers in military, religious and organizational settings is not a mistake from the point of view of the memes involved. They are recognizing their kin and directing resources towards their kin accordingly.

From the point of view of the genes of the human host the resource allocation does look like more of a mistake. Or rather: it benefits some humans at the expense of others. The genes in the factory bosses no doubt benefit if their workers behave like sisters in an ant nest - and cooperate for the common good. However the genes in the factory workers are probably not doing so well. The workers probably wouldn't wear the blue suits unless they were made to do so - and might treat their co-workers worse as a result. In short they are victims of manipulation who put up with the situation because they are wage slaves who can't find better jobs.

In other cases, the uniform wearers seem to don their robes enthusiastically. Sometimes, religions folk and tribe members seem to love the garb that makes them all appear as though they are brothers and sisters. It seems pretty speculative to argue that their DNA benefits from this - but you can imagine cases where the interests of the memes involved and the interests of the host DNA are more closely aligned. In such cases, cultural kin selection can be invoked to explain the cooperation that results - without the situation necessarily being a "big mistake" from the perspective of the host DNA.

In the paper, Joe continues:

This version of the “big mistake hypothesis” (Boyd and Richerson, 2002a) suggests that, because our psychology supposedly evolved in small groups with high degrees of interrelatedness, kin selection (along with reciprocity, see next section) favored a psychology in humans that is designed to generously bestow benefits on members of their groups. According to this idea, natural selection apparently neglected to provide humans with the ability to distinguish kin and long-term reciprocators from anonymous strangers in ephemeral interactions. Thus, in the novel world of large-scale, complex societies, this once adaptive psychological propensity misfires, giving us large-scale cooperation (Tooby and Cosmides, 1989).

That hypothesis might explain why we don't have better defenses against kinship-related manipulation. However it simply isn't the main kinship-based explanation of why humans are so cooperative! Humans mostly cooperate with other humans which they share memes with because they are manipulated into doing so - via cultural kin selection. The manipulation is typically mediated by memes, but it often serves the interests of the genes of other humans. For example, the politicians and generals spread the patriotism memes - but it's the infantrymen that are killed by them. It isn't a "big mistake" for the memes involved - or for the humans that benefit from the manipulation.

Joe criticizes this so-called "big mistake hypothesis", apparently writes off kin selection and then goes on to advocate group selection for much of the rest of the paper. To his credit, Joe does actually acknowledge the equivalence of kin selection and group selection in this paper (section 4.3). However, his treatment of kin selection seems shoddy to me.

If you want to reject decades of work on kin selection, and advocate an alternative approach, IMO,
you should first understand how to apply the standard approach and then go on to explain why your approach is better. In the case of cultural evolution, this involves kin selection applied to cultural variation. IMO, Joe Henrich fails at this project on the first hurdle, by apparently not understanding how to apply the main rival theory: kin selection. This seems like a weak position to launch an alternative approach from.

The modern wave of group selection in the social sciences is built on shoddy foundations like these. Those involved didn't properly understand how to apply kin selection to memes. They thought that kin selection didn't work - for all the wrong reasons. We can now see that they were mistaken. I think that the next issue is how best to clean up the mess they have created.